Many masters swimmers have legitimate injuries or disabilities which may allow them make adjustments to their strokes legally in competition. If a swimmer can not swim a stroke they will typically not enter the event in competition for obvious reasons.
What if a swimmer appears to be taking advantage of USMS exemptions for an event? It seems to happen in less popular events like 200 Butterfly and 400 IM.
Are swimmers that determined to be a USMS Top Ten Swimmer?
